Aft berth leak

[junaido]

Newly minted owner of '86 c34 here. So I have been noticing a leak in the aft berth from the protective cover/ doghouse right under the steering pedestal. I undid all the screws on it today but it is stuck on there pretty good and not budging -- yet I can see the leaks. I am not sure if previous owner bedded it with butyl tape alone or some marine adhesive/caulk. I can see copious amounts of butyl tape in the joint. However, usually butyl tape doesn't adhere which is why it is recommended for through-bolted hardware. This thing is not through-bolted but it is stuck so hard I can't pry it off without risking breaking it. What is the recommended way to seal it? Should I address the leak at the protective cover or at the steering pedestal base? Any ideas on how to fix this leak? Thanks.

[KWKloeber]

Where did you get info that butyl rubber 'doesn't stick'?  Not sure what that property (not sticking) would have to do with thru hull fasteners? 

Butyl rubber is what keeps your windshield stuck to your automobile.

See
https://pbase.com/mainecruising/butyl_tape

[Noah]

What is the "protective cover" you are speaking of? If you have a MKI boat there is nothing (that I know of) in the cockpit floor. The MK1.5-MKII have the emergency tiller cover but not MKIs?? Or, are you talking about the "doghouse" cover over the steering pulleys accessed from inside the cabin? those are just screwed up into the cockpit floor from below. You can remove it but no good way to fix any leaks from below. You need to stop leaks from the outside. 

[junaido]

Yes the "dog house". I think this article https://www.sailnet.com/threads/bedding-deck-hardware-with-butyl-tape.63554/ mentions that butyl tape is not a glue. Whatever the case may be, how do I "unstick" it so I can rebed it?

[junaido]

Pic. Also, there are a couple of screws that are stripped and just spin without tightening. It is my understanding that butyl tape needs "compression" to make a good seal.

[Jim Hardesty]

Whatever the case may be, how do I "unstick" it so I can rebed it?

That cover should not be bedded. I have some foam, draft sealer, there.  Think the bedding was the PO attempt at fixing a leak.  You have a bit of a chore to remove the cover.  Remove all the screws, if they spin pull them out, then as gently as possible work around the edges with a putty knife, you may need to find or modify one to go straight into the bedding, gentle heat may help.  Good thing is that the bedding should only be half inch or so wide.  That should get the cover off.  Then clean up everything and look up for your leak.   Stripped out screw holes can be filled and drilled again.
Hope this helps,
Jim

[glennd3]

That is just a cover. Remove screws and slowly pry away with a putty knife. As Noah said leaks are from the outside.

[BJeansson]

Junaido,
We have the same leak on our 1990 MK1.25.
Once you remove the inside cover my guess would be that your leak, or at least your first place to trouble shoot would be the bedding for the NavPod pedestal in front of your steering column. That is where my leak is and I will re-bed with Butyl tape.

When we inspected the boat in August the aft cabin was dry but when we took possession in November  the aft mattress was soaked on the bottom. The PO was surprised as he did not have any leak in the aft cabin. I suppose someone had "jerked" hard on the pedestal and caused the leak.

We plan to use an underlayment under the mattress, anyone has any good idea for a well functioning underlayment without having to invest in the Frohlic system or similar?

1990 MK1.25 #1024 SR/WK M35
Rock Hall, MD

[scgunner]

Junaido,

It looks like the PO attempted some kind of off the wall kind of fix, it's things like this that give POs a bad name. Aside from using some kind of unnecessary bedding compound he also put in a bunch of extra screws, mine is held in place with four screws, one at each corner. It's also got a gray insulating tape. When the screws are removed the cover pops right off.

Is this cover where the leak is coming from? I had an aft cabin leak which was caused by a leak in the water tank and showed at the bottom of the wooden panel.

[Jon W]

Junaido, The below troubleshooting may not help this leak, but while you're in the area here's something to check -

Do you have a water tank behind that bulkhead on the 1986? If you do -

when you get the dog house off look at the water tank in the area where the dog house screw holes are in the bulkhead. The bottom row of screws holding the dog house to the bulkhead can wear a hole in the tank if they're too long. I replaced the wood screws with machine screws and installed t-nuts in the wood bulkhead.

[Noah]

BJeansson - i use Hypervent material under my bunks as an "underlayment".
https://www.defender.com/product.jsp?id=1818021

[junaido]

Thanks for all the replies. I don't think there are any water tanks in that area. There is a large bladder tank under the aft berth and one forward in the v-berth. I will try heat/putty knife approach. The steering pedestal  is most likely the source of the leak. It is secured to the cockpit floor with four large screws.

[Jon W]

My 1987 has an aft tank behind the bulkhead, but I wasn't sure if the 1986 had a tank there so thought I'd mention the possibility.

FYI - A non water leak thing to check in this same area are the pins for the steering cable pulleys. Are they brass or SST? If brass you should plan to change them to SST. If you haven't already, read through the Critical Upgrades listed on the main page of the Forum. Very helpful list for a new owner.

[glennd3]

As long as you are back there you may want to remove both wood panels and look around. Fuel tank, thru hulls, water tank........

[Noah]

If you do remove the teak plywood athwartship bulkhead, and There is not a water tank there, please post a picture. I am curious as to what Catalina used that "future aft water tank space" for. Lots of space there. You could possibly make a locker out of it? For your info, pics of my 1990.